Basil recognizes that master-slave relationships are a given among men and he doesn't condemn or reject them in principle. In some cases he even justifies them, understanding then that the "master" isn't the one who exploits the subject for his own benefit, but the one who decides for him for the benefit of all:

"Some, oppressed by the power of others, have been reduced to the yoke of slavery, like captives of war, or others, because of their poverty, as the Egyptians [it seems like he should have said Hebrews instead of Egyptians] under Pharaoh, or, according to a wise and arcane provision, disadvantaged children have been sentenced to serve the more clever and gifted ones, something an impartial observer would not consider a condemnation, but a benefit. Since the one who, through lack of understanding, does not have rule over himself by nature, it is more useful for him to make himself the property of another so that, led by the reason of the owner, he ressembles the chariot that receives the charioteer or the ship that has the captain at the helm." (20:51)

However, in light of what has been said of the concept of 'communion' in Basil, isn't this definition of 'relationality' contradictory? Doesn't Basil argue precisely that 'communion' excludes 'subordination', and that nor is subordination benevolent and, in principle, beneficial to both sides? Indeed, we find on this point in my opinion an example of the necessary transformation of human relations in the light of divine ones:

"They [those who claim that the Spirit is neither slave nor master, but free] insult the dogmas of theology with human examples and try to fit the custom of the world, which maintains sharp differences in dignity, to the ineffable divine nature, not perceiving that, among humans, no one is a slave by nature." (20:51)

In this short paragraph, we distinguish the following three statements: 1. that the customs of the world are not criteria for assessing divine realities, 2. that differences in dignity don't fit into the ineffable divine nature, and 3. that among human beings no one is a slave [meaning 'slave of another man'] by nature. Precisely because God is Lord (the one Lord), all master-slave relationships between men are ultimately delegitimized (here we find the seeds of modern consciousness of equality in dignity and human rights, and their ultimate foundation):

"So, therefore, while one is called master and the other slave, both due to the equal respect we owe each other and the fact that we are like possessions of the One who created us, we are fellow servants. If this is so, who could be excluded from servitude? Because of the fact itself of being created, one is made a servant. Creatures don't really rule over each other (...)." (20.51)